Which of the following electrolytes is present in human saliva?

Choose the correct answer among the following:
$(a)$ Gastric juice contains
$(i)$ pepsin,lipase and rennin
$(ii)$ trypsin,lipase and rennin
$(iii)$ trypsin,pepsin and lipase
$(iv)$ trypsin,pepsin and renin
$(b)$ Succus entericus is the name given to
$(i)$ a junction between ileum and large intestine
$(ii)$ intestinal juice
$(iii)$ swelling in the gut
$(iv)$ appendix

Choose the correct option:
$(1)$ The calorific value of fat is higher than that of glucose.
$(2)$ Premolars are absent in the dental formula of a human child.

Given below are two statements:
$Statement I$: The cardiac sphincter prevents regurgitation of food from the stomach to the duodenum.
$Statement II$: The pyloric sphincter regulates the flow of food from the oesophagus to the stomach.
In the light of the above two statements, choose the most appropriate answer from the options given below.

We feel sleepy just after taking meals because

Match the following and choose the correct combination from the options given:

Column-$I$	Column-$II$
$(A)$ Ptyalin	$(1)$ Lipids
$(B)$ Pepsin	$(2)$ Starch
$(C)$ Steapsin	$(3)$ $DNA$
$(D)$ Nuclease	$(4)$ Proteins